It is a natural illusion that makes us think of each century as exhibiting the continuous development of one tendency of mind through a series of stages whose differences are only of secondary importance, and, on the other hand, to regard the steps from one century to another as corresponding to some marked transition of thought, as if the world had been suddenly precipitated into a new sphere of existence. For some purposes a rough generalization of this kind, that breaks at stated intervals the continuity of time, may, perhaps, be convenient. When, however, we begin to look at things more closely, we discover that it is impossible thus to cut through the historical connection of events, as it were, “with a hatchet.” We discover, for example, that the characteristics of the eighteenth century were strongly marked only in one period of it; and that what we call the spirit of the nineteenth century was born some time before the year 1800, and has never quite prevailed over other tendencies. At the same time, there is an important difference indicated by these two loosely used names, and as it is always easier to define things by contrast, it may help us to make our subject more definite to consider what they mean. I It is too late now to “abuse the eighteenth century,” which had its good and evil, like other periods. It is commonly conceived as the era of individualism and analysis, the era of logical enlightenment and sceptical criticism; and, again, as the era of liberation from groundless superstitions and fictitious claims of authority; the era in which mankind seemed for the first time to throw off the weight of the past and to enter without fear upon the enjoyment of their earthly heritage. The science of Newton had given the last blow to the astronomy that made the earth the centre of the universe. It had undermined and discredited the simple theology that explained the whole material world as a cosmos arranged for the supply of human needs. At the same time, the progress of biology was bringing man to a consciousness that as a physical being he is only _primus inter pares_ in the animal kingdom, and the decay of religious belief was making him realize his finitude, the limits of his natural existence, as, perhaps, he had never done before, at least never since the beginning of the Christian era. Earth seemed to be disconnected from heaven, and the human race thrown upon its own resources. By the new enlightenment all powers, ecclesiastical or political, were stripped of the mysterious sanctity that had once invested them. “The nimbus was taken away from the heads of the gods and rulers of the world.” Every authority that claimed man’s homage was weighed in the scales of the understanding, and, so weighed, every such authority was found wanting. The State had come to be regarded as only a collection of individuals who had agreed to live together under a ruler deriving all his claims from their